U.S. patent number 6,688,313 [Application Number 09/814,779] was granted by the patent office on 2004-02-10 for electrical smoking system and method.
This patent grant is currently assigned to Philip Morris Incorporated. Invention is credited to Mary Ellen Counts, William James Crowe, Traci L. Franklin, Patrick H. Hayes, A. Clifton Lilly, Jr., Susan E. Wrenn.
United States Patent |
6,688,313 |
Wrenn , et al. |
February 10, 2004 |
Electrical smoking system and method
Abstract
An electrical smoking system comprising a cigarette and an
electric lighter, wherein the cigarette comprises a tubular tobacco
mat partially filled with material tobacco so as to define a filled
tobacco rod portion and an unfilled tobacco rod portion. The
cigarette and the lighter are mutually arranged so that when the
cigarette is received in the lighter, the electrical heater element
of the lighter at least partially superposes at least a portion of
the filled tobacco rod portion. The cigarette and the lighter are
also mutually arranged so that when the cigarette is received in
the lighter, the free end of the cigarette is occluded. The
cigarette includes a zone of perforations at a location along the
filled tobacco rod portion, with the cigarette being free of
perforations along the unfilled tobacco rod portion. An apparatus
for perforating a cigarette which can be smoked in an electrical
smoking device includes a drum link-up assembly and a laser
perforating apparatus. The apparatus can be used in a method of
perforating a tobacco rod of the cigarette prior to assembly of the
tobacco rod to a filter rod via tipping paper. In the method, a
tobacco rod is supplied to the drum link-up assembly wherein the
tobacco rod is moved from a combining apparatus to a tipping
apparatus which attaches the tobacco rod to a filter rod by tipping
paper. In making the cigarettes with a tobacco rod and a filter
rod, a combining apparatus forms a continuous tobacco rod which is
cut into 2-up tobacco rods.
Inventors: |
Wrenn; Susan E. (Chesterfield,
VA), Lilly, Jr.; A. Clifton (Chesterfield, VA), Franklin;
Traci L. (Mechanicsville, VA), Hayes; Patrick H.
(Chester, VA), Counts; Mary Ellen (Richmond, VA), Crowe;
William James (Chester, VA) |
Assignee: |
Philip Morris Incorporated (New
York, NY)
|
Family
ID: |
27392899 |
Appl.
No.: |
09/814,779 |
Filed: |
March 23, 2001 |
Current U.S.
Class: |
131/194; 131/360;
131/361 |
Current CPC
Class: |
A24D
1/20 (20200101); A24C 5/01 (20200101); A24C
5/606 (20130101); A24C 5/478 (20130101); A24F
40/20 (20200101) |
Current International
Class: |
A24C
5/47 (20060101); A24C 5/00 (20060101); A24C
5/60 (20060101); A24F 47/00 (20060101); A24F
013/04 () |
Field of
Search: |
;131/194,281,360,364,344,331,361,365 |
References Cited
[Referenced By]
U.S. Patent Documents
|
|
|
3496945 |
February 1970 |
Tomkin |
3637447 |
January 1972 |
Berger et al. |
5060671 |
October 1991 |
Counts et al. |
5144962 |
September 1992 |
Counts et al. |
5372148 |
December 1994 |
McCafferty et al. |
5388594 |
February 1995 |
Counts et al. |
5498855 |
March 1996 |
Deevi et al. |
5499636 |
March 1996 |
Baggett, Jr. et al. |
5505214 |
April 1996 |
Collins et al. |
5591368 |
January 1997 |
Fleischhauer et al. |
5665262 |
September 1997 |
Hajaligol et al. |
5666976 |
September 1997 |
Adams et al. |
5692291 |
December 1997 |
Deevi et al. |
5692525 |
December 1997 |
Counts et al. |
5865185 |
February 1999 |
Collins et al. |
5902501 |
May 1999 |
Nunnally et al. |
5954979 |
September 1999 |
Counts et al. |
6040560 |
March 2000 |
Fleischhauer et al. |
|
Other References
Notification of Transmittal of International Preliminary
Examination Report for PCT/US01/09302, dated Aug. 29, 2002. .
Written Opinion dated Mar. 25, 2002 for International Application
No. PCT/US01/09302..
|
Primary Examiner: Walls; Dionne A.
Attorney, Agent or Firm: Burns, Doane, Swecker & Mathis,
LLP
Parent Case Text
This application claims priority under 35 U.S.C. .sctn.119 to
Provisional Application No. 60/191,455 filed in the U.S. on Mar.
23, 2000; Provisional Application No. 60/191,460 filed in the U.S.
on Mar. 23, 2000; and Provisional Application No. 60/191,461 filed
in the U.S. on Mar. 23, 2000; the entire contents of which are
hereby incorporated by reference.
Claims
What is claimed is:
1. An electrical smoking system comprising: a cigarette comprising
a tubular tobacco mat partially filled with tobacco material so as
to define a filled tobacco rod portion and an unfilled tobacco rod
portion, said filled tobacco rod portion being adjacent a free end
of said cigarette; and a lighter comprising an electrical heater
element and a system for electrically actuating said heater
element, said lighter arranged to at least partially receive said
cigarette; said cigarette and said lighter being mutually arranged
so that when the cigarette is received in said lighter, said
electrical heater element of the lighter at least partially
superposes at least a portion of the filled tobacco rod portion;
said cigarette and said lighter being mutually arranged so that
when the cigarette is received in said lighter, said free end of
said cigarette is occluded; said cigarette including a zone of
perforations at a first location along said filled tobacco rod
portion; said cigarette being free of perforations along said
unfilled tobacco rod portion.
2. The electrical smoking system as claimed in claim 1, wherein
said lighter further comprises an air admission passage and an
arrangement operative at a location along said air admission
passage to produce a pressure drop in the range of 10 to 40 mm
water.
3. The electrical smoking system as claimed in claim 2, wherein
said lighter further comprises a puff sensor having a sensitivity
to a change in pressure in the range of 10 to 40 mm water.
4. The system as claimed in claim 1, said lighter further
comprising an air admission passage and an arrangement operative at
a location along said air admission passage to produce a pressure
drop in the range of 20 to 30 mm water.
5. The system as claimed in claim 4, said lighter further
comprising a puff sensor having a sensitivity to a change in
pressure in the range of 20 to 30 mm water.
6. The system as claimed in claim 5, wherein said cigarette has a
resistance to draw of approximately 20 to 25 mm water.
7. The system as claimed in claim 4, wherein said lighter further
comprises an air flow deflector arranged to direct air drawn into
said lighter toward a cigarette receiving location within said
lighter, the air flow deflector directing the air in a
circumferential zone around the cigarette at the location of the
zone of perforations.
8. The system as claimed in claim 7, wherein at least a portion of
said lighter adjacent said cigarette receiving location is
constructed of a metal, including at least said air flow
deflector.
9. The system as claimed in claim 1, wherein said lighter further
comprises a flow deflector arranged to direct air drawn into said
lighter toward a cigarette receiving location within said lighter,
the air flow deflector directing the air in a circumferential zone
around the cigarette at the location of the zone of
perforations.
10. The system as claimed in claim 9, wherein at least a portion of
said lighter adjacent said cigarette receiving location is
constructed of a metal, including at least said air flow
deflector.
11. A cigarette of an electrical smoking system, comprising a
tobacco rod and a filter tipping attached to a tipped end portion
of said tobacco rod, said tobacco rod comprising: a tubular tobacco
mat partially filled with tobacco material so as to define a filled
tobacco rod portion and an unfilled tobacco rod portion, said
filled tobacco rod portion being adjacent a free end of said
cigarette; said cigarette including a zone of perforations at a
first location along said filled tobacco rod portion; said
cigarette being free of perforations along said unfilled tobacco
rod portion.
12. The cigarette as claimed in claim 11, said tobacco rod further
comprising a cigarette wrapper disposed about said tubular tobacco
mat, said perforations extending at least partially through said
wrapper and said mat.
13. The cigarette as claimed in claim 12, wherein said cigarette is
adapted to receive thermal treatment along a length portion of said
tobacco rod corresponding to a heater footprint of an electrical
lighter, said length portion spaced a predetermined distance from
said free end portion of said tobacco rod, said first location of
said zone of perforations being spaced from said free end of said
tobacco rod a first distance approximately equal to said
predetermined distance.
14. The cigarette as claimed in claim 12, wherein said cigarette is
adapted to receive thermal treatment along a length portion of said
tobacco rod corresponding to a heater footprint of an electrical
lighter, said length portion spaced a predetermined distance from
said free end portion of said tobacco rod, said first location of
said zone of perforations being spaced from said free end of said
tobacco rod a first distance greater than said predetermined
distance.
15. The cigarette as claimed in claim 12, wherein said cigarette is
adapted to receive thermal treatment along a length portion of said
tobacco rod corresponding to a heater footprint of an electrical
lighter, said length portion spaced a predetermined distance from
said free end portion of said tobacco rod, said first location of
said zone of perforations being spaced from said free end of said
tobacco rod a first distance less than said predetermined
distance.
16. The cigarette as claimed in claim 12, further comprising a
plurality of circumferentially spaced-apart holes in said tubular
tobacco mat at a second location along said filled tobacco rod
portion, said wrapper covering said mat holes.
17. The cigarette as claimed in claim 16, wherein said tubular
tobacco mat comprises a tubular base web and a layer of tobacco
material disposed along an interior of said tubular base web; said
mat holes extending through said base web and said layer of tobacco
material.
18. The cigarette as claimed in claim 16, wherein said mat holes
are approximately 1 mm in diameter and 6 in number, arranged in a
row and said zone of perforations comprises one or two rows of
perf-holes, each row having 12 perf-holes.
19. The cigarette as claimed in claim 16, wherein said second
location of mat holes is spaced from said free end of said tobacco
rod a second distance of approximately 7 mm and said zone of
perforations comprises at least one row of 12 perf-holes spaced
approximately 12 mm from said free end.
20. The cigarette as claimed in claim 16, wherein a second
perforation zone is established at a third location along said
tobacco rod; said second location of mat holes being between said
first and third locations, said second location of mat holes is
optionally spaced from said free end of said tobacco rod a first
distance of approximately 7 mm and said perforation zones are
optionally spaced from said free end of said tobacco rod
approximately 4 and 12 mm, respectively.
21. The cigarette as claimed in claim 11, said tobacco rod further
comprising a cigarette wrapper disposed about said tubular tobacco
mat, said perforations extending at least partially through said
wrapper and said mat.
22. The cigarette as claimed in claim 21, wherein said cigarette is
adapted to receive thermal treatment along a length portion of said
tobacco rod corresponding to a heater footprint of an electrical
lighter, said length portion spaced a predetermined distance from
said free end portion of said tobacco rod, said first location of
said zone of perforations being spaced from said free end of said
tobacco rod a first distance approximately equal to said
predetermined distance.
23. The cigarette as claimed in claim 21, wherein said cigarette is
adapted to receive thermal treatment along a length portion of said
tobacco rod corresponding to a heater footprint of an electrical
lighter, said length portion spaced a predetermined distance from
said free end portion of said tobacco rod, said first location of
said zone of perforations being spaced from said free end of said
tobacco rod a first distance greater than said predetermined
distance.
24. The cigarette as claimed in claim 21, wherein said cigarette is
adapted to receive thermal treatment along a length portion of said
tobacco rod corresponding to a heater footprint of an electrical
lighter, said length portion spaced a predetermined distance from
said free end portion of said tobacco rod, said first location of
said zone of perforations being spaced from said free end of said
tobacco rod a first distance less than said predetermined
distance.
25. The cigarette as claimed in claim 21, wherein a second
perforation zone is established at a third location along said
tobacco rod; a second location of mat holes in said tubular tobacco
mat being between said first and third locations, said second
location of mat holes is optionally spaced from said free end of
said tobacco rod a first distance of approximately 7 mm and said
perforation zones are optionally spaced from said free end of said
tobacco rod approximately 4 and 12 mm, respectively.
26. The cigarette as claimed in claim 11, wherein said tobacco rod
includes a tubular body at the tipped end portion of the tobacco
rod; and said filter tipping includes a free flow filter adjacent
said tubular body and a mouthpiece filter adjacent said free flow
filter.
27. The cigarette as claimed in claim 26, wherein said tubular body
has a smaller inside diameter than said free flow filter.
Description
FIELD OF INVENTION
The present invention relates to electrical smoking systems and
methods of increasing delivery in electrical smoking systems.
BACKGROUND OF INVENTION
Traditional cigarettes are consumed by lighting an end of a wrapped
tobacco rod and drawing air predominately through the lit end by
suction at a mouthpiece end of the cigarette. Traditional
cigarettes deliver smoke as a result of combustion, during which a
mass of tobacco is combusted at temperatures which often exceeds
800.degree. C. during a puff. The heat of combustion releases
various gaseous combustion products and distillates from the
tobacco. As these gaseous products are drawn through the cigarette,
they cool and condense to form a smoke containing the tastes and
aromas associated with smoking. Traditional cigarettes produce
sidestream smoke during smoldering between puffs. Once lit, they
must be fully consumed or be discarded. Relighting a traditional
cigarette is possible but is usually an unattractive proposition to
a discerning smoker for subjective reasons (flavor, taste,
odor).
In an electrical smoking system, it is desirable to deliver smoke
in a manner that meets the smokers experiences with more
traditional cigarettes, such as an immediacy response (smoke
delivery occurring immediately upon draw), a desired level of
delivery (which correlates with FTC tar level), together with a
desired resistance to draw (RTD) and consistency from puff to puff
and from cigarette to cigarette.
Commonly assigned U.S. Pat. Nos. 5,388,594 and 5,692,525 disclose
electrical smoking systems and methods of manufacturing a
cigarette, which patents are incorporated by reference. The former
patent describes an electrical smoking system including a novel
electrically powered lighter and a novel cigarette that cooperates
with the lighter. The preferred embodiment of the lighter therein
included a plurality of metallic serpentine heaters disposed in a
configuration that slidingly receives a tobacco rod portion of the
cigarette. The preferred embodiment of the cigarette therein
comprised a tobacco-laden tubular carrier, a cigarette paper
overwrapped about the tubular carrier, an arrangement of
flow-through filter plugs at a mouthpiece end of the carrier and a
filter plug at the free (distal) end of the carrier. The cigarette
and the lighter were configured such that when the cigarette is
inserted into the lighter and as individual heaters are actuated
for each puff, localized charring occurs at spots about the
cigarette in the locality where each heater was bearing against the
cigarette (hereinafter referred to as a "heater footprint" or "char
zones"). Once all the heaters had been actuated, the cigarette is
discarded.
In the latter patent, the cigarette includes a tobacco plug and the
cigarette and the heater fixture are mutually configured such that
the heater footprints (char zones) at least partially overlap the
tobacco plug as well as a hollow portion of the tobacco rod. Such
arrangement provides an immediacy of response from the early
initiation of pyrolysis at the void, together with inclusion of a
fuller flavor contribution from the plug of tobacco(s).
It has been desirous to produce an electrical smoking system of the
type described above that produces delivery levels of substantially
greater than 3 milligrams tar (FTC). A greater segment of smokers
prefer the higher levels of delivery from their more traditional
cigarettes of choice. Obtaining such levels of delivery in
electrical smoking systems has heretofore been a challenging
proposition.
For example, the previously described electrical smoking systems
are battery operated, so that the total energy expended per puff
needs to be kept at acceptable levels. Too much power application
in the heater elements during a puff can lead to burn-throughs and
sometimes undesired degrees of combustion.
In systems such as taught in commonly assigned U.S. Pat. No.
5,692,525, in which heater footprints (char zones) at least
partially overlap a hollow portion of the tobacco rod and partially
overlap a tobacco plug, burn-throughs will usually first appear in
the region of the hollow portion of the tobacco rod. Upon such
occurrence, the smoke tends to be hotter than the other puffs, with
less contribution of the fuller flavor usually generated by the
heating of the tobacco plug portion of the cigarette rod.
Consistency in the smoking experience are compromised if
burn-throughs are not somehow avoided.
In commonly assigned U.S. Pat. No. 5,388,594, the smoked portion of
the tobacco rod is preferably entirely hollow and the heater
footprint is entirely superposed over a the hollow portion of the
tobacco rod. Burn-throughs in the "wholly hollow" system of U.S.
Pat. No. 5,388,594 tend to make the smoke all the more hot and/or
harsh tasting. Providing expedients to increase delivery in the
"wholly hollow" system of U.S. Pat. No. 5,388,594, such as
providing perforations as suggested at column 10, lines 36-51
thereof, aggravate the risks of burn-throughs, with adverse
consequences upon taste and consistency.
Resistance to draw (RTD) of traditional cigarettes is the pressure
required to force air through the full length of a cigarette at the
rate of 17.5 ml per second. RTD is usually expressed in inches or
millimeter of water. Smokers have certain expectations when drawing
upon a traditional cigarette in that too little RTD or too much can
detract from smoking enjoyment. More traditional cigarettes of
moderate delivery have RTD's generally within the range of
approximately 100 to 130 mm water.
Establishing a desired RTD in electrical smoking systems is
complicated by the circumstance that in smoking systems such as
shown in U.S. Pat. Nos. 5,388,594 and 5,692,525, air is first drawn
through passages within the cigarette lighter before being drawn
out through the cigarette. The filter tipping of the cigarettes of
those systems are preferably flow-through and/or low particulate
efficiency filters so as to minimize loss of whatever smoke is
produced. Such filters produce little pressure drop and therefore
do not contribute much RTD. Consequently, prior practices have
included the establishment of RTD (or pressure drop) predominantly
in the lighter portion of the electrical smoking system, such as
with an annular frit (porous body) adjacent the air admission port
of the lighter as taught in commonly assigned U.S. Pat. No.
5,954,979. Because pressure drop varies widely with any change in
size of the constriction, it has been found that the use of frits
or other forms of tiny flow constrictions in the lighter body must
be manufactured with care. It therefore adds expense and other
production and quality concerns. Furthermore, tiny flow passages
are prone to clog, particularly in lighters wherein any smoke is
allowed to linger after completion of a puff.
OBJECTS AND SUMMARY OF INVENTION
An object of the present invention is to provide a cigarette
containing cut filler or other form of shredded tobacco, which
cigarette is adapted to cooperate with an electrical lighter and
render satisfying levels of delivery and taste.
Another object of the present invention is to provide a cigarette
for an electrical smoking system which includes cut filler, yet
provides improved consistency in delivery from puff to puff.
Another object of the present invention is to provide a cigarette
adapted for use in electrical smoking systems, which cigarette is
resistive to breakage during the withdrawal of the cigarette from
the lighter thereof.
It is still a further object of this invention to provide a novel
cigarette that is operative with an electrical lighter and
conducive to cost-effective methods of manufacture, even at
production speeds.
These and other objects are achieved with the present invention
which provides an electrical smoking system comprising a cigarette
and an electric lighter, wherein the cigarette comprises a tubular
tobacco mat partially filled with material tobacco so as to define
a filled tobacco rod portion and an unfilled tobacco rod portion.
The filled tobacco rod portion is situated adjacent a free end of
said cigarette. The lighter comprises an electrical heater element
and a system for electrically actuating said heater element, with
the lighter being arranged to at least partially receive said
cigarette. The cigarette and the lighter are mutually arranged so
that when the cigarette is received in the lighter, the electrical
heater element of the lighter at least partially superposes at
least a portion of the filled tobacco rod portion. The cigarette
and the lighter are also mutually arranged so that when the
cigarette is received in the lighter, the free end of the cigarette
is occluded. Furthermore, the cigarette includes a zone of
perforations at a location along the filled tobacco rod portion,
with the cigarette being free of perforations along the unfilled
tobacco rod portion.
By such arrangements and others, the delivery (total particulate
matter ("TPM") per FTC testing methodology) of the electrical
smoking system may be increased without producing a hot,
harsh-tasting smoke. Importantly, the enhanced delivery is achieved
without overdriving the heater element of the lighter. The elevated
delivery is achieved without additional load upon the batteries of
the lighter and without driving the heater element to excessive
peak temperatures.
A further aspect is provision of cooperative features within the
lighter and the cigarette such that a large majority of the
resistance to draw of the smoking system originates along the side
walls of cigarette, with a lesser portion originating from flow
passages within the lighter.
A further aspect of the present invention is provision of an
air-flow deflector along an interior portion of the lighter to
favorably direct air toward the cigarette.
In addition to the above, the invention provides an apparatus for
perforating a tobacco rod prior to assembly of the tobacco rod to a
filter rod via tipping paper, comprising a drum link-up assembly
adapted to transfer a tobacco rod from a combining apparatus to a
tipping apparatus wherein the tobacco rod is attached to a filter
rod by tipping paper; and a laser perforating apparatus adapted to
bum one or more holes in an outer surface of the tobacco rod while
the tobacco rod is in the drum link-up assembly.
According to one embodiment of the invention, the laser perforating
apparatus includes a lens arrangement which bums at least one
circumferentially extending row of perforations around the tobacco
rod. According to another embodiment, the drum link-up assembly
includes a drum having flutes on an outer surface thereof, the
laser perforating apparatus being adapted to rotate the tobacco rod
about its axis while pulsing a laser to burn the at least one row
of perforations into the tobacco rod as the tobacco rod is rolled
from one flute to an adjacent flute. If desired, the laser
perforating apparatus can include a beam splitter which separates a
beam from a pulsed laser into at least two beams which bum at least
two rows of elongated holes into the tobacco rod to form a laser
perforated tobacco rod. Preferably, the drum link-up assembly
comprises at least one rotating drum having flutes sized to carry
2-up tobacco rods.
According to a preferred embodiment, the drum link-up assembly
includes a series of drums which transfer 2-up tobacco rods to the
tipping machine, the drums including a catch drum, a transfer drum,
a swash plate drum, a laser drum, a cutting drum, and a separating
drum, the catch drum receiving 2-up tobacco rods from a delivery
device of a combining apparatus and delivering the 2-up tobacco
rods to the transfer drum, the transfer drum delivering the 2-up
tobacco rods to the swash plate drum, the swash plate drum aligning
the 2-up tobacco rods and delivering the aligned 2-up tobacco rods
to the laser drum, the laser drum orienting the 2-up tobacco rods
such that the laser perforating apparatus bums at least two
longitudinally spaced apart rows of perforations on each of the
2-up tobacco rods, the laser drum delivering the 2-up tobacco rods
to the cutting drum, the cutting drum cutting the 2-up tobacco rods
into a pair of tobacco rods of unit length and delivering the pair
of tobacco rods to the separating drum at which the pair of tobacco
rods are spaced longitudinally apart, the separating drum
delivering the tobacco rods to an assembly drum of a tipping
apparatus at which the pair of tobacco rods are combined with a
2-up filter rod by placing the 2-up filter rod between the pair of
spaced apart tobacco rods.
The apparatus can further comprise a combining machine which
includes means for wrapping a tobacco plug and a free-flow filter
plug within a tobacco matt and an outer paper wrapper to form a
continuous tobacco rod, the combining machine including a cutting
apparatus which cuts the continuous tobacco rod into 2-up tobacco
rod segments, the laser perforating apparatus being adapted to burn
perforating holes at locations on the 2-up tobacco rods such that
the perforating holes pass through the outer paper wrapper and the
tobacco matt and into the tobacco plugs of the 2-up tobacco rod
segments. Further, the apparatus can include a tipping apparatus
which includes means for attaching the perforated tobacco rods to
filter rods by locating a 2-up filter rod in a space between a pair
of the perforated tobacco rods, wrapping tipping paper around the
2-up filter rod such that the tipping paper overlaps portions of
the perforated tobacco rods, gluing ends of the tipping paper
together, and cutting the 2-up filter rods to produce a pair of
cigarettes. If desired, the tipping apparatus can include a laser
perforating station at which the cigarettes are provided with
additional perforation holes, the laser perforating station
including a lens arrangement which provides at least one
circumferentially extending row of the additional perforations at a
location along the tobacco rod.
The invention also provides a method of perforating a tobacco rod
prior to assembly of the tobacco rod to a filter rod via tipping
paper, comprising supplying a tobacco rod to a drum link-up
assembly wherein the tobacco rod is moved from a combining
apparatus to a tipping apparatus wherein the tobacco rod is
attached to a filter rod by tipping paper, and forming a perforated
tobacco rod by actuating a laser perforating apparatus so as to
burn one or more perforating holes in an outer surface of the
tobacco rod while the tobacco rod is in the drum link-up
assembly.
Another object of the present invention is to establish a method of
manufacturing with high speed production machinery a cigarette of
the type operable with an electric lighter and containing cut
filler.
It is another object of the present invention to provide a
cigarette suited for consumption with a lighter of an electrical
smoking system and a method of manufacturing same, wherein the
cigarette is not subjected to forces which would tend to collapse
or break the cigarette during its manufacture.
It is still a further object of this invention to provide a novel
cigarette that is operative with an electrical lighter and a
cost-effective method of manufacturing the cigarette.
These objects and other advantages are provided by the present
invention which provides a cigarette operable with an electrically
operated lighter, which lighter includes a plurality of electrical
heaters, with each of the heaters being adapted to, either
singularly or in concert, to generate tobacco smoke by applying
heat to the cigarette along portions of the cigarette adjacent the
heaters as a result of activation of the heater or heaters.
In accordance with one aspect of the present invention, the
cigarette comprises a tubular tobacco web, wherein a first portion
of the tubular tobacco web is filled with a column of tobacco,
preferably in the form of cut filler, and a second portion of the
tubular tobacco web is left unfilled or hollow so as to define a
void in the tobacco column.
More particularly, the aforementioned cigarette preferably
comprises a tobacco rod formed from a tubular tobacco web and a
plug of tobacco located within the tubular tobacco web. The tobacco
rod is adapted to be slidingly received by an electrical heater
fixture such that the heater elements locate alongside the tobacco
rod at a location between the free end and an opposite end of the
tobacco rod. Preferably the plug (or column) of tobacco extends
from the free end of the tobacco rod to a location that is spaced
from the opposite end of the tobacco rod so as to define a void (or
hollow portion) adjacent the opposite end.
Still another aspect of the present invention is to provide a
filler containing cigarette that is operative with an electrical
lighter, which cigarette includes a tobacco rod having a free-flow
filter and a filler-free rod portion adjacent the free flow filter
so as to promote consistent aerosol production.
A preferred embodiment of the present invention provides a method
of manufacturing such cigarettes, wherein the method comprises the
steps of establishing a succession of 2-up hollow plugs in
alternating, spaced apart relation to 2-up tobacco plugs and
wrapping the succession of plugs in a tobacco web and overwrap so
as to produce a continuous rod; severing the resultant continuous
rod to establish associated pairs of singular tobacco rod plugs;
separating the members of each associated pair of singular tobacco
rod plugs so as to establish a space therebetween; placing a 2-up
filter tipping plug in the space between each a pair of separated,
singular tobacco rod plugs; bringing the 2-up filter tipping plug
and said singular tobacco rod plugs together into an abutting
relation; and subsequently wrapping tipping paper about the placed
2-up filter tipping plug together with adjacent portions of the
abutting singular tobacco rod plugs to form a 2-up cigarette rod;
and severing the 2-up cigarette into individual cigarettes.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present invention are well
understood by reading the following detailed description in
conjunction with the drawings in which like numerals indicate
similar elements and in which:
FIG. 1 is a perspective view of a smoking system in accordance with
a preferred embodiment of the present invention with a cigarette of
the system inserted into the electrically operated lighter;
FIG. 2 is a perspective view of the smoking system of FIG. 1, but
with the cigarette withdrawn from the lighter upon conclusion of a
smoking;
FIG. 3A is a partial perspective detail view of portions of the
heater fixture of FIG. 1, including wavy hairpin heater elements
and portions of a preferred air admission system;
FIG. 3B is a sectional side view of a preferred heater fixture
which includes the wavy hairpin heater elements of FIG. 3A;
FIG. 3C is a side view of the cigarette shown in FIG. 4 inserted
into the heater fixture of FIG. 6, with the latter being shown in
cross-section;
FIG. 4 is a detail perspective view of a preferred embodiment of
the cigarette shown in FIG. 1, with certain components of the
cigarette being partially unraveled;
FIG. 5 is a schematic, block-diagram of a preferred control circuit
for the lighter shown in FIGS. 1 and 2;
FIG. 6 is a side cross sectional view of the cigarette shown in
FIG. 4 wherein a free end of the cigarette is in contact with a
stop piece in the lighter;
FIG. 7 is a representation of steps and apparatus in a preferred
process of manufacturing tobacco rod portions of the cigarette
shown in FIG. 4 in accordance with a preferred method of
manufacturing such cigarettes;
FIGS. 8A-8E are successive cross-sectional views at lines A--A to
E--E, respectively at the garniture in FIG. 7, as components of the
cigarette shown in FIG. 4 progress through the garniture;
FIG. 9 is a diagram of a tipping apparatus which is adapted to
attach filter tipping to the tobacco rod portions produced in
accordance with the process in FIG. 7;
FIGS. 10A and 10B are diagrams showing the relative movement and
placement of cigarette pieces during execution of the tipping
operation of the preferred method of manufacturing cigarettes of
the type shown in FIG. 4;
FIG. 11 shows a perspective side view of a laser perforating
apparatus which can be used to burn perforation holes in tobacco
rods in accordance with the invention;
FIG. 12 is a perspective view of the apparatus shown in FIG. 11 but
from an opposite side thereof;
FIG. 13 is a cross sectional view of a portion of the apparatus
shown in FIG. 11;
FIG. 14 is a cross sectional view of a beam splitting arrangement
which can be used in the apparatus shown in FIG. 1; and
FIG. 15 is a schematic diagram showing a combining apparatus
directly linked to a tipping apparatus by a transfer apparatus in
accordance with the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, a preferred embodiment of the present
invention provides a smoking system 21 which preferably includes a
partially-filled, filter cigarette 23 and a reusable lighter 25.
The cigarette 23 is adapted to be inserted into and removed from a
cigarette receiver 27 which is open at a front end portion 29 of
the lighter 25. Once the cigarette 23 is inserted, the smoking
system 21 is used in much the same fashion as a more traditional
cigarette, but without lighting or smoldering of the cigarette 23.
The cigarette 23 is discarded after one or more puff cycles.
Preferably, each cigarette 23 provides a total of eight puffs (puff
cycles) or more per smoke; however it is a matter of design
expedient to adjust to a lesser or greater total number of
available puffs. In the preferred embodiment, the cigarette 23
includes at least one peripheral ring of perforations 12 located
adjacent the free end 15 of the cigarette 23 and optionally a
second ring or rings of perforations 14 and optionally a plurality
of holes 16 underneath the outer wrapper of the cigarette 23.
Further particulars of the smoking system is described also in the
commonly assigned, U.S. Pat. Nos. 5,388,594; 5,505,214; 5,591,368
and 5,499,636, all which are hereby incorporated by reference in
their entireties.
The lighter 25 includes a housing 31 having front and rear housing
portions 33 and 35. One or more batteries 35a are removably located
within the rear housing portion 35 and supply energy to a heater
fixture 39 which includes a plurality of electrically resistive,
heating elements 37 (shown in FIGS. 3A-C). The heating elements 37
are arranged within the front housing portion 33 to slidingly
receive the cigarette 23 along an intermediate portion of the
cigarette receiver 27. A stop 183 located at the base 300 of the
heater fixture 39 defines a terminus of the cigarette receiver
27.
A control circuit 41 in the front housing portion 33 selectively
establishes electrical communication between the batteries 35a and
one or more the heater elements 37 during execution of each puff
cycle. The preferred embodiment of the present invention includes
details concerning an air management system for effecting the
admission and routing of air within the lighter, including aspects
which are discussed in greater detail beginning with reference to
FIG. 3C.
Still referring to FIGS. 1 and 2, preferably the rear portion 35 of
the lighter housing 31 is adapted to be readily opened and closed,
such as with screws or snap-fit components, so as to facilitate
replacement of the batteries. If desired, an electrical socket or
contacts may be provided for recharging the batteries in a charger
supplied with house current or the like. Preferably, the front
housing portion 33 is removably joined to the rear housing portion
35, such as with a dovetail joint or a socket fit.
The batteries 35a are sized to provide sufficient power for the
heaters 37 to function as intended and preferably comprise a
replaceable and rechargeable type. Alternate sources of power are
suitable, such as capacitors. In the preferred embodiment, the
power source comprises four nickel-cadmium battery cells connected
in series with a total, non-loaded voltage in the range of
approximately 4.8 to 5.6 volts. The characteristics of the power
source are, however, selected in view of the characteristics of
other components in the smoking system 21, particularly the
characteristics of the heating elements 37. Commonly assigned U.S.
Pat. No. 5,144,962, hereby incorporated by reference, describes
several types of power sources useful in connection with the
smoking system of the present invention, such as rechargeable
battery sources and power arrangements which comprise a battery and
a capacitor which is recharged by the battery.
Referring specifically to FIG. 2, preferably, the circuitry 41 is
activated by a puff-actuated sensor 45 that is sensitive to either
changes in pressure or changes in rate of air flow that occur upon
initiation of a draw on the cigarette 23 by a smoker. The
puff-actuated sensor 45 is preferably located within the front
housing portion 33 of the lighter 25 and is communicated with a
space inside the heater fixture 39 adjacent the cigarette 23 via a
port 45a extending through a side wall portion 182 of the heater
fixture 39. A puff-actuated sensor 45 suitable for use in the
smoking system 21 is described in commonly assigned U.S. Pat. No.
5,060,671 and U.S. Pat. No. 5,388,594, the disclosures of which are
incorporated herein by reference. The puff sensor 45 preferably
comprises Fujikura Ltd. Model FSS-02 PG. Another suitable sensor is
a Model 163PCO1D35 silicon sensor, manufactured by the MicroSwitch
division of Honeywell, Inc., Freeport, Ill. Flow sensing devices,
such as those using hot-wire anemometry principles, have also been
successfully demonstrated to be useful for actuating an appropriate
one of the heater elements 37 upon detection of a change in air
flow. Once actuated by the sensor 45, the control circuitry 41
directs electric current to an appropriate one of the heater
elements 37.
An indicator 51 is provided at a location along the exterior of the
lighter 25, preferably on the front housing portion 33, to indicate
the number of puffs remaining in a smoke of a cigarette 23. The
indicator 51 preferably includes a seven-segment liquid crystal
display. In the preferred embodiment, the indicator 51 displays a
segmented image which correlates with the digit "8" when a
cigarette detector 57 detects the presence of a cigarette in the
heater fixture 39. The detector 57 preferably comprises an
inductive coil 1102 adjacent the cigarette receiver 27 of the
heater fixture 39 and electric leads 1104 that communicate the coil
1102 with an oscillator circuit within the control circuitry 41.
The cigarette 23 internally bears a foil ring or the like which can
affect inductance of the coil winding 1102 such that whenever a
cigarette 23 is inserted into the receiver 27, the detector 57
generates a signal to the circuitry 41 indicative of the cigarette
being present. The control circuitry 41 in turn provides a signal
to the indicator 51. The display of the digit "8" on the indicator
51 reflects that the eight puffs provided on each cigarette 23 are
available, i.e., no puff cycle has been undertaken and none of the
heater elements 37 have been activated to heat the cigarette 23.
After the cigarette 23 is fully smoked, the indicator displays the
digit "0". When the cigarette 23 is removed from the lighter 25,
the cigarette detector 57 no longer detects a presence of a
cigarette 23 and the indicator 51 is turned off.
The operation and details of the inductive cigarette detector 57 is
provided in commonly assigned U.S. Pat. No. 5,902,501, which is
incorporated herein by reference in its entirety. Other detectors
may be employed instead of the above-described one for the detector
57, such as a Type OPR5005 Light Sensor, manufactured by OPTEX
Technology, Inc., 1215 West Crosby Road, Carrollton, Tex.
75006.
In the alternative to displaying the remainder of the puff count,
the detector display may instead be arranged to indicate whether
the system is active or inactive ("on" or "off").
As one of several possible alternatives to using the above-noted
cigarette detector 57, a mechanical switch (not shown) may be
provided to detect the presence or absence of a cigarette 23 and a
reset button (not shown) may be provided for resetting the
circuitry 41 when a new cigarette is inserted into the lighter 25,
e.g., to cause the indicator 51 to display the digit "8", etc.
Power sources, circuitry, puff-actuated sensors, and indicators
useful with the smoking system 21 of the present invention are
described in commonly assigned, U.S. Pat. Nos. 5,060,671; 5,388,594
and 5,591,368, all which are incorporated herein by reference.
Referring now to FIGS. 3A and 3B, the front housing portion 33 of
the lighter 25 encloses a substantially cylindrical heater fixture
39 whose heater elements 37 slidingly receive the cigarette 23. The
heater fixture 39 is adapted to support an inserted cigarette 23 in
a fixed relation to the heater elements 37 such that the heater
elements 37 are positioned alongside the cigarette 23 at
approximately the same location along each newly inserted cigarette
23. In the preferred embodiment, the heater fixture 39 includes
eight mutually parallel heater elements 37 which are disposed
concentrically about the axis of symmetry of the cigarette receiver
27. The locations where each heater element 37 bears against (or is
in thermal communication with) a fully inserted cigarette 23 is
referred to herein as the heater footprint or char zone 42. In the
preferred embodiment, the char zone may extend approximately 14 mm
in length, beginning approximately 9 mm from the free-end 15 of the
cigarette 23. Of course, these relations may be varied amongst
different lighter and cigarette designs. In another model for
example, the char zone 42 extends from 12 mm to 23 mm from the
free-end of the cigarette 23.
Referring also to FIG. 3C, to assure consistent placement of the
heating elements 37 relative to each cigarette 23 from cigarette to
cigarette, the heater fixture 39 is provided with a base portion
300 having a cupped stop-piece 183 against which the free end 15 of
the cigarette 23 is urged during its insertion into the cigarette
receiver 27 of the lighter 25. The cupped shape of the stop-piece
183 is configured to close-off (occlude) the free end 15 of the
cigarette 23 upon full insertion of the cigarette 23 so that air
cannot be drawn through the free end 15, but instead only from
along the side walls of the cigarette 23.
Still referring to FIGS. 3A and 3B, most preferably the heater
elements 37 are of a design referred to herein as a wavy hairpin
heater element 37, wherein each heater element 37 includes at least
first and second serpentine, elongate members 53a and 53b which are
adjoined at an end portion (tip) 54. The tips 54 are adjacent the
opening 55 of the cigarette receiver 27. The opposite ends 56a and
56b of each heater element 37 are electrically connected to the
opposite poles of the power source 35a as selectively established
by the controller 41. More specifically, an electrical pathway
through each heater fixture 37 is established, respectively,
through a terminal pin 104, a connection 121 between the pin 104
and a free end portion 56a of one of the serpentine members 53a,
through at least a portion of the tip 54 to the other serpentine
member 53b and its end portion 56b. Preferably, an integrally
formed, common connection ring 110 provides a common electrical
connection amongst all the end portions 56b of the elongate member
53b. In the preferred embodiment, the ring 110 is connected to the
positive terminal of the power source 35a (or common) through a
connection 123 between the ring 110 and a pin 105. Further details
of the construction and establishment of electrical connections in
the heater fixture 39 are illustrated and described in the commonly
assigned U.S. Pat. Nos. 5,060,671; 5,388,594 and 5,591,368, all
which are incorporated herein by reference.
The heater portions 53a, 53b and 54 establish what is here referred
to as a heater blade 120.
Other preferred designs of the heater fixture 39 include heater
elements in the form of a straight hairpin heater elements 37,
which are set forth in the commonly assigned U.S. Pat. No.
5,591,368 and "singular serpentine" heater elements each which are
set forth in commonly assigned U.S. Pat. No. 5,388,594, said
patents being incorporated herein by reference in their
entireties.
Additional heater fixtures 37 that are operable as part of the
lighter 25 include those disclosed in commonly assigned, U.S. Pat.
No. 5,665,262; and commonly assigned, U.S. Pat. No. 5,498,855, all
which are incorporated herein by reference in their entireties.
Preferably, the heaters 37 are individually energized by the power
source 35a under the control of the circuitry 41 to heat the
cigarette 23 preferably eight times at spaced locations about the
periphery of the cigarette 23. The heating renders eight puffs from
the cigarette 23, as is commonly achieved with the smoking of a
more traditional cigarette. It may be preferred to activate more
than one heater simultaneously for one or more or all of the
puffs.
Referring now to FIG. 4, the cigarette 23 is preferably constructed
in accordance with the preferred embodiment set forth in commonly
assigned, U.S. Pat. No. 5,499,636, herein incorporated by reference
in its entirety.
Referring particularly to FIGS. 3A, 3B, and 3C, preferably the puff
sensor 45 is communicated to the interior of the heater fixture 39
through a port 45a. Preferably, the port 45a is located adjacent
the base portion 300 of the heater fixture 39. Such location
minimizes the risk that the port 45a and adjacent passageways
leading thereto through the body of the heater fixture 39 would
become clogged by the debris or smoke condensates.
The heater fixture 39 includes an air inlet port 1200, which
communicates with a manifold 1202 that is at least partially
defined by a perforated annulus 1204 and the body of the receiver
27. The annulus 1204 includes preferably four holes 1206 of
approximately 0.029 inch diameter for effecting a minimal pressure
drop as air is drawn into the lighter through the air inlet port
1200 and the manifold 1202. The size and number of the holes 1206
may be varied, but such are configured to provide sufficient
pressure drop that upon drawing action upon an inserted cigarette
23, a pressure drop is induced upon the air entering the lighter
such that the puff sensor 45 is operative to recognize initiation
of a puff. In the preferred embodiment, the holes 1206 of the
annulus 1204 induce an RTD of approximately 25 mm water plus or
minus 5 mm. The range of pressure drop induced at the annulus 1204
should be selected such that it is within the range of pressure
drop detectable by the pressure sensor 45, but minimized to that
need so that the remainder of desired RTD (Resistance To Draw) is
effected predominantly by the cigarette 23. In the preferred
embodiment, a grand total RTD of 4 to 5 inches water (100 to 130 mm
water) is desired and approximately 25 mm of that is produced at
the annulus 1204. Accordingly, the RTD of the cigarette 23 is
preferably in the range of approximately 75 to 105 mm water RTD,
when inserted in lighter 25 and the induced pressure drop of the
lighter 25 is approximately 25 mm water. Adjustment of cigarette
RTD in accordance with the present invention includes provision of
and adjustment of the number and extent of perforations 12 (and
optionally 14) in the filled portion 88 of the cigarette 23.
Advantageously, the holes 1206 of the annulus 1204, being located
adjacent the receiver 27, is positioned away from sources of debris
and condensates which might otherwise tend to clog the holes
1206.
Air that has been drawn into the lighter upon initiation of a puff
enters alongside the cigarette with a substantial longitudinal
(axial) velocity component toward the base portion 300 of the
heater fixture 300. It has been discovered that a flow deflector or
annular air-swoop 1210 adjacent the base portion 300 enhanced smoke
output (delivery) of the system 21 by directing at least a portion
of the entering airflow back toward the inserted cigarette 23. Not
wishing to be bound by theory, it is believed that the air-swoop
1210 tends to direct airflow toward regions of the cigarette 23
bearing perforations 12. Preferably, the annular air-swoop 1210 is
located relative to a fully inserted cigarette 23 such that the
air-swoop 1210 circumscribes the general location along the
cigarette 23 of the perforations 12.
It has discovered that the functioning of the air-swoop 1210 is
improved if it is constructed from metal, or alternatively, all
body portions of the heater fixture 39 are constructed from a metal
such as a stainless steel, or at least those portions of the heater
fixture 39 that are disposed adjacent an inserted cigarette 23.
Such provision can provide an increase of delivery of 1 mg TPM
(FTC).
The cigarette 23 comprises a tobacco rod 60 and a filter tipping
62, which are joined together with tipping paper 64.
The tobacco rod 60 of the cigarette 23 preferably includes a
tobacco web or "mat" 66 which has been folded into a tubular
(cylindrical) form about a free-flow filter 74 at one of its ends
and a tobacco plug 80 at the other. In the alternative, a plug of
cellulose acetate might be used in place of the tobacco plug 80.
The longitudinal (axial) extent of the tobacco plug 80 defines a
tobacco filled portion 88 of the partially-filled cigarette 23.
An overwrap 71 is intimately enwrapped about the tobacco web 66 and
is held together along a longitudinal seam as is common in
construction of more traditional cigarettes. The overwrap 71
retains the tobacco web 66 in a wrapped condition about a free-flow
filter 74 and a tobacco plug 80.
The tobacco web 66 itself preferably comprises a base web 68 and a
layer of tobacco material 70 located along the inside surface of
the base web 68. At the tipped end of the tobacco rod 60, the
tobacco web 66 together with the overwrap 71 are wrapped about the
tubular free-flow filter plug 74. Preferably, the tobacco plug 80
is constructed separately from the tobacco web 66 and comprises a
relatively short column of cut filler tobacco that preferably has
been wrapped within and retained by a plug wrap 84.
As a general matter, the length of the tobacco plug 80 is
preferably set relative to the total length of the tobacco rod 60
such that a void 90 is established along the tobacco rod 60 between
the free-flow filter 74 and the tobacco plug 80. The void 90
corresponds to an unfilled portion of the tobacco rod 60 and is in
immediate fluid communication with the tipping 62 through the free
flow filter 74 of the tobacco rod 60.
The tipping 62 preferably comprises a free-flow filter 92 located
adjacent the tobacco rod 60 and a mouthpiece filter plug 94 at the
distal end of the tipping 62 from the tobacco rod 60. Preferably,
the free-flow filter 92 is tubular and transmits air with very
little pressure drop. Other low efficiency filters of standard
configuration could be used instead, however. The inside diameter
for the free flow filter 92 is preferably at or between 2 to 6 mm
and is preferably greater than that of the free flow filter 74 of
the tobacco rod 60.
The mouthpiece filter plug 94 closes off the free end of the
tipping 62 for purposes of appearance and, if desired, to effect
some filtration, although it is preferred that the mouthpiece
filter plug 94 comprise a low efficiency filter of preferably about
15 to 25 percent efficiency.
Still referring to FIG. 4, preferably, the partially-filled
cigarette 23 includes at least one row of perforations 12 at a
location adjacent the free end 15 of the tobacco rod portion of the
cigarette 23. Preferably, the row of perforations 12 are twelve
holes in count and may be formed as slits 17 (perf-holes) at a 400
microsecond pulse width setting of a Hauni Model 500-1 on-line
laser perforator system. Each perf-hole 17 of the row of
perforations 12 preferably extends through the outer wrapper 71,
through the tobacco mat 66 and the plug wrap 84.
Referring now also FIG. 2, preferably, the row of perforations 12
is located at or adjacent to end portion 42a of the char zone 42.
Such placement is believed to promote entrance of heated air into
the tobacco plug 80 and create other additional favorable effects
upon pyrolysis during a puff cycle such that delivery (TPM-FTC) is
enhanced.
To further improve delivery, additional row or rows of perforations
14 comprising perf holes 17 as previously described may be provided
at a location along the filled portion 88 of the tobacco rod 60
preferably, at a location superposed, or at least partially
superposed, by the heater char zone or footprint 42 and/or
alternatively, adjacent the free end 15 of the cigarette 23. In the
latter alternate embodiment, the second row of perforations 14 is
established at approximately 4 mm from the free end 15 of the
cigarette 23. Either or both of the perforation rows 12 or 14 may
comprise a single row or a dual row of perf-holes 17.
The number and extent of perf-holes 17 are resolved in accordance
with two countervailing considerations. The addition of rows of
perforation 12, 14 as described above contributes to enhanced
delivery of the cigarette 23. However, each additional row of
perforations 12, 14 reduces RTD along the side walls of the
cigarettes 23. Preferably, the grand total RTD of the electrical
smoking system 21 should provide the smoker a resistance to draw
approximately the same as that experience with traditional
cigarettes of approximately 4 to 5 inches water (approximately
100-130 mm water) or thereabouts, 80-130 mm water.
It has been found that at a total energy input of 23.8 Joules to a
heater element 37, a cigarette 23 bearing a dual row of
perforations 12 at a location 12 mm from the free end 15 of the
cigarette (dual rows of 12 holes each) can produce deliveries
substantially greater than 3 milligrams TPM (FTC). Further
deliveries may be obtained by addition of a second row or rows of
perforations 14.
However, each additional row of perf-holes 17 lowers RTD, which
preferably is to remain at or above 100 mm water for the whole
system 21. Should one find that for a given cigarette 23,
additional delivery is desired yet the RTD level is nearing its
lower limit, additional delivery can be obtained by provision of a
plurality of circumferentially spaced-apart holes 16 placed in the
mat 66 itself. Preferably, the mat holes 16 are each approximately
one mm in diameter and preferably 6 in number so that the requisite
tensile strength of the mat material 66 is maintained and may
withstand machine manufacturing. Preferably, these holes are formed
by an opposing punch-and-die roller assembly 240 as shown in FIG. 7
which is located along the feed-path of the mat in the cigarette
making operation, as is described in U.S. Pat. No. 5,666,976, which
patent is hereby incorporated by reference in its entirety.
For example, in the preferred embodiment, the mat holes 16 are
preferably produced utilizing opposing rollers bearing
hole-punching elements. Other devices may be employed instead, such
as a disk or endless belt arrangement located along the feed path
of the mat, with the disk or endless belt including multiple
hole-punching dies which are brought to approximate feed speed of
the mat by the movement of the disk or endless belt.
Preferably, the holes 16 in the mat 66 are covered by the outer
wrapper 71. Preferably, any row of perforations 12, 14 is displaced
away from the location of the row of mat holes 16 so that they do
not overlap. In a preferred embodiment, the mat holes 16 are
located approximately 7 mm from the free-end 15 of the cigarette
23, and a dual row of perforations 12 is established approximately
12 mm from the end 15 of the cigarette 23. So arranged, the
cigarette achieves a 6 mg TPM (FTC) or more. Advantageously, the
mat holes 16 can contribute an additional delivery to the cigarette
23 without the same extent of reduction in RTD as is experienced
with each addition of row of perf-holes 17. Accordingly, one may
utilize the rows of perforations 12, 14 to approximate desired
delivery levels for the cigarette 23, with the mat holes 16 being
used to adjust or increase delivery with a lesser effect on
RTD.
More traditional cigarettes exhibit a resistance to draw (RTD) of
approximately 80 mm to 130 mm water. The lighter of the electrical
smoking system according to the present invention when tested
without a cigarette exhibits an RTD of approximately 20-30 mm
water. The cigarettes according to the present invention having the
laser perforations and mat holes as taught herein exhibit an RTD of
approximately 20-30 mm water when drawn upon by themselves (outside
of the lighter of the electrical smoking system), but when
inserted, the electrical smoking system (the lighter and the fully
inserted cigarette) generate an RTD of approximately 50-75 mm
water. Table 1 sets forth results of RTD measurements for
cigarettes without perforations or mat holes, cigarettes with mat
holes only and cigarettes with mat holes and a double row of laser
perforations. The cigarettes had a circumference of 24 to 25 mm,
the mat holes consisted of a single row of 6 mat holes 7 mm from
the end of the cigarettes and the double row of perforations
consisted of 12 holes in each row at a location about 12 mm from
the end of the cigarette with the rows about 1 mm apart.
TABLE 1 Circumference RTD-OE RTD-BE Run (mm) (mm) (mm) 1 24.58 32
875 2 24.53 35 551 3 24.57 30 57 - circumference and RTD values are
average of results obtained for 25 cigarettes tested during each
run OE RTD of cigarettes tested in smoking machine with tobacco end
of cigarettes open to atmosphere BE RTD of cigarettes tested in
smoking machine with tobacco end of cigarettes blocked by cup
fitted over cigarette end
In order to compare various aspects of cigarettes having various
combinations of perf-holes 17 and mat holes 16 to cigarettes having
no perforations or holes, test cigarettes having circumferences of
24 to 25 mm were constructed having the features set forth in Table
2.
The control cigarette had no perforations nor mat holes and test
cigarettes 1-7 included laser perforations located 12 mm from the
tobacco end of the cigarette and/or mat holes located 7 mm from the
tobacco end of the cigarette.
The test cigarettes with laser perforations included either a
single row of evenly spaced laser cut slits extending
circumferentially around the cigarette or a double row of such
laser perforations wherein the rows are located approximately 1 mm
apart.
The test cigarettes with mat holes included a single row of six
evenly spaced mat holes having diameters of 1 mm circumferentially
spaced about the cigarette. As shown in the test results, the
sample having a double row of 12 laser holes and the six 1 mm
diameter mat holes provided tobacco smoke having the highest TPM.
In the tests, the electrical smoking system was mounted in a
conventional cigarette smoking machine that measures that portion
of the smoke which is collected on a pad, its tar, nicotine and
water. During the tests, the cigarette smoking machine was operated
under FTC smoking conditions wherein a 2 second puff is taken every
60 seconds for a total of 8 puffs.
TABLE 2 Tar, Nicotine, Water, Description TPM, mg/cig. mg/cig.
mg/cig mg/cig Control 5.24 2.18 0.15 2.91 1 single row of 6 5.67
2.36 0.18 3.12 laser perforations 2 single row of 12 5.25 2.15 0.17
2.92 laser perforations 3 double row of 6 5.28 2.08 0.15 2.73 laser
perforations per row 4 double row of 12 5.57 2.06 0.17 3.34 laser
perforations per row 5 single row of 6 5.41 2.25 0.18 2.97 laser
perforations and 6 mat holes 6 double row of 12 6.44 2.39 0.19 3.86
laser perforations and 6 mat holes 7 6 mat holes only 5.56 2.07
0.16 3.33
Referring now to FIGS. 2 and 5, the electrical control circuitry 41
of the lighter 25 includes a logic circuit 195, which preferably
comprises a micro-controller or an application specific, integrated
circuit (or "ASIC"). The control circuitry also includes the
cigarette sensor 57 for detecting the insertion of a cigarette 23
in the cigarette receiver 27 of the lighter 25, the puff sensor 45
for detecting a draw upon the inserted cigarette 23, the LCD
indicator 51 for indicating the number of puffs remaining on a
cigarette, the power source 35a and a timing network 197.
The logic circuit 195 may comprise any conventional circuit capable
of implementing the functions discussed herein. A
field-programmable gate array (e.g., a type ACTEL A1280A FPGA PQFP
160, available from Actel Corporation, Sunnyvale, Calif.) or a
micro controller can be programmed to perform the digital logic
functions with analog functions performed by other components. An
ASIC or micro-controller can perform both the analog and digital
functions in one component. Features of control circuitry and logic
circuitry similar to the control circuit 41 and logic circuit 195
of the present invention are disclosed, for example, in commonly
assigned, U.S. Pat. Nos. 5,388,594; 5,505,214; 5,591,368; and
5,499,636, all which are hereby incorporated by reference in their
entireties. Further details are also provided in the copending,
commonly assigned U.S. Pat. No. 6,040,560, hereby incorporated by
reference in its entirety.
In the preferred embodiment, eight individual heater elements 37
are connected to a positive terminal of the power source 35a and to
ground through corresponding field effect transistor (FET) heater
switches 201-208. Individual (or selected) ones of the heater
switches 201-208 will turn on under control of the logic circuit
195 through terminals 211-218, respectively, during execution of a
power cycle by the logic circuit 195. The logic circuit 195
provides signals for activating and deactivating particular ones of
the heater switches 201-208 to activate and deactivate the
corresponding heater element 37 of the heater fixture 39.
The logic circuit 195 cooperates with the timing circuit 197 to
precisely execute the activation and deactivation of each heater
element 37 in accordance with a predetermined total cycle period
("T.sub.total ") and to precisely divide each total cycle period
into a predetermined number of phases, with each phase having its
own predetermined period of time ("t.sub.phase "). In the preferred
embodiment, the total cycle period T.sub.total has been selected to
be 1.6 seconds (so as to be less than the two-second duration
normally associated with a smoker's draw upon a cigarette, plus
provision for margin) and the total cycle period T.sub.total is
divided preferably into two phases, a first phase having a
predetermined time period ("t.sub.phase 1 ") of 1.0 seconds and a
second phase having a predetermined time period ("t.sub.phase 2 ")
of 0.6 seconds. The total cycle period T.sub.total, the total
number of phases and the respective phase periods are parameters,
among others, that are resolved in accordance with the teachings
which follow for establishing within the control circuit 41, a
capacity to execute a power cycle that precisely duplicates a
preferred thermal interaction ("thermal profile" or
"thermo-histogram") between the respective heater element 37 and
adjacent portions of the cigarette 23. Additionally, once the
preferred thermo-histogram is established, certain parameters
(preferably, duty cycles within each phase) are adjusted
dynamically by the control circuit 41 so as to precisely duplicate
the predetermined thermo-histogram with every power cycle
throughout the range of voltages v.sub.in encompassed by the
aforementioned battery discharge cycle.
The puff-actuated sensor 45 supplies a signal to the logic circuit
195 that is indicative of smoker activation (i.e., a continuous
drop in pressure or air flow over a sufficiently sustained period
of time). The logic circuit 195 includes a debouncing routine for
distinguishing between minor air pressure variations and more
sustained draws on the cigarette to avoid inadvertent activation of
heater elements in response to errant signal from the puff-actuated
sensor 45. The puff-actuated sensor 45 may include a piezoresistive
pressure sensor or an optical flap sensor that is used to drive an
operational amplifier, the output of which is in turn used to
supply a logic signal to the logic circuit 195. Puff-actuated
sensors suitable for use in connection with the smoking system
include a Model 163PC01D35 silicon sensor, manufactured by the
MicroSwitch division of Honeywell, Inc., Freeport, Ill., or a type
NPH-5-02.5G NOVA sensor, available from Lucas-Nova, Fremont,
Calif., or a type SLP004D sensor, available from SenSym
Incorporated, Sunnyvale, Calif.
The cigarette sensor 57 is located at the cigarette receiver 27 and
supplies a signal to the logic circuit 195 that is indicative of
insertion of a cigarette 23 in the lighter 25. Optionally a second
sensor may be located adjacent the stop 183 so as to determine
whether the cigarette has been fully inserted into the receiver
27.
In order to conserve energy, it is preferred that the puff-actuated
sensor 45 and the cigarette sensor 57 be cycled on and off at low
duty cycles (e.g., from about a 2 to 10% duty cycle). For example,
it is preferred that the puff actuated sensor 45 be turned on for a
1 millisecond duration every 10 milliseconds. If, for example, the
puff actuated sensor 45 detects pressure drop or air flow
indicative of a draw on a cigarette during four consecutive pulses
(i.e., over a 40 millisecond period), the puff actuated sensor
sends a signal through a terminal 221 to the logic circuit 195. The
logic circuit 195 then sends a signal through an appropriate one of
the terminals 211-218 to turn an appropriate one of the FET heater
switches 201-208 ON.
Similarly, the cigarette sensor 57 is preferably turned on for a 1
millisecond duration every 10 milliseconds. If, for example, the
cigarette sensor 57 detects four consecutive reflected pulses,
indicating the presence of a cigarette 23 in the lighter 25, the
light sensor sends a signal through terminal 223 to the logic
circuit 195. The logic circuit 195 then sends a signal through
terminal 225 to the puff-actuated sensor 45 to turn on the
puff-actuated sensor. The logic circuit 195 also sends a signal
through terminal 227 to the indicator 51 to turn it on. The
above-noted modulation techniques reduce the time average current
required by the puff actuated sensor 45 and the cigarette sensor
57, and thus extend the life of the power source 37.
The logic circuit 195 includes a PROM (programmable read-only
memory) 301, which includes preferably at least two data bases or
"look-up tables" 302 and 304, and optionally, a third data base
(look-up table) 306 and possibly a fourth look-up table 307. Each
of the look-up tables 302, 304 (and optionally 306, 307) converts a
signal indicative of battery voltage v.sub.in to a signal
indicative of the duty cycle ("dc.sub.1 " for the first phase and
"dc.sub.2 " for the second phase) to be used in execution of the
respective phase of the immediate power cycle. Third and fourth
look-up tables 306 and 307 function similarly.
Upon initiation of a power cycle, the logic circuit receives a
signal indicative of battery voltage v.sub.in, and then references
the immediate reading v.sub.in to the first look-up table 302 to
establish a duty cycle dc.sub.1 for the initiation of the first
phase of the power cycle. The first phase is continued until the
timing network 197 provides a signal indicating that the
predetermined time period of the first phase (t.sub.phase 1) has
elapsed, whereupon the logic circuit 195 references v.sub.in and
the second look-up table 304 and establishes a duty cycle dc.sub.2
for the initiation the second phase. The second phase is continued
until the timing network 197 provides a signal indicating that the
predetermined time period of the second phase (t.sub.phase 2) has
elapsed, whereupon the timing network 197 provides a shut-off
signal to the logic circuit 195 at the terminal 229. Optionally,
the logic circuit 195 could initiate a third phase and establish a
third duty cycle dc.sub.3, and the shut-off signal would not be
generated until the predetermined period of the third phase
(t.sub.phase 3) had elapsed. A similar regimen could optionally be
established with a fourth phase (t.sub.phase 4). The present
invention could be practiced with additional phases as well.
Although the present invention can be practiced by limiting
reference to the look-up tables to an initial portion of each phase
to establish a duty cycle to be applied throughout the substantial
entirety of each phase, a refinement and the preferred practice is
to have the logic circuit 195 configured to continuously reference
v.sub.in together with the respective look-up tables 302, 303, 306
and 307 so as to dynamically adjust the values set for duty cycles
in response to fluctuations in battery voltage as the control
circuit progresses through each phase. Such device provides a more
precise repetition of the desired thermo-histogram.
Other timing network circuit configurations and logic circuits may
also be used, such as those described in the commonly assigned,
U.S. Pat. Nos. 5,388,594; 5,505,214; 5,591,368; 5,499,636; and
5,372,148, all which are hereby incorporated by reference in their
entireties.
During operation, a cigarette 23 is inserted in the lighter 25 and
the presence of the cigarette is detected by the cigarette sensor
57. The cigarette sensor 57 sends a signal to the logic circuit 195
through terminal 223. The logic circuit 195 ascertains whether the
power source 35a is charged or whether the immediate voltage is
below an acceptable minimum v.sub.in min. If, after insertion of a
cigarette 23 in the lighter 25, the logic circuit 195 detects that
the voltage of the power source 35a is too low, below v.sub.in min,
the indicator 51 blinks and further operation of the lighter will
be blocked until the power source 35a is recharged or replaced.
Voltage of the power source 35a is also monitored during firing of
the heater elements 37 and the firing of the heater elements 37 is
interrupted if the voltage drops below a predetermined value.
If the power source 35a is charged and voltage is sufficient, the
logic circuit 195 sends a signal through terminal 225 to the puff
sensor 45 to determine whether a smoker is drawing on the cigarette
23. At the same time, the logic circuit 195 sends a signal through
the terminal 227 to the indicator 51 so that the LCD will display
the digit "8", reflecting that eight puffs are available.
When the logic circuit 195 receives a signal through terminal 221
from the puff-actuated sensor 45 that a sustained pressure drop or
air flow has been detected, the logic circuit 195 sends a signal
through terminal 231 to the timer network 197 to activate the timer
network, which then begins to function phase by phase in the manner
previously described. The logic circuit 195 also determines, by a
downcount routine, which one of the eight heater elements is due to
be heated and sends a signal through an appropriate terminal
211-218 to turn an appropriate one of the FET heater switches
201-208 ON. The appropriate heater stays on while the timer
runs.
When the timing network 197 sends a signal through terminal 229 to
the logic circuit 195 indicating that the timer has stopped
running, the particular ON FET heater switch 211-218 is turned OFF,
thereby removing power from the particular heater element 37. The
logic circuit 195 also downcounts and sends a signal to the
indicator 51 through terminal 227 so that the indicator will
display that one less puff is remaining (e,g., "7", after the first
puff). When the smoker next puffs on the cigarette 23, the logic
circuit 195 will turn ON another predetermined one of the FET
heater switches 211-218, thereby supplying power to another
predetermined one of the heater elements. The process will be
repeated until the indicator 51 displays "0", meaning that there
are no more puffs remaining on the cigarette 23. When the cigarette
23 is removed from the lighter 25, the cigarette sensor 57
indicates that a cigarette is not present, and the logic circuit
195 is reset.
Other features, such as those described in U.S. Pat. Nos.
5,505,214; 5,388,594; and 5,372,148 which are incorporated by
reference, may be incorporated in the control circuitry 41 instead
of or in addition to the features described above. For example, if
desired, various disabling features may be provided. One type of
disabling feature includes timing circuitry (not shown) to prevent
successive puffs from occurring too close together, so that the
power source 35a has time to recover. Another disabling feature
includes means for disabling the heater elements 37 if an
unauthorized product is inserted in the heater fixture 39. For
example, the cigarette 23 might be provided with an identifying
characteristic that the lighter 25 must recognize before the
heating elements 37 are energized.
Referring now to FIG. 6, the cigarette 23, as constructed in
accordance with the preferred embodiment of the present invention,
comprises a tobacco rod 60 and a filter tipping 62, which are
joined together with tipping paper 64. During manufacture of the
cigarette, perforation holes 263 can be provided in one or more
locations in the outer surface of the tobacco rod 60.
The partially-filled, filler cigarette 23 preferably has an
essentially constant diameter along its length and, which like more
traditional cigarettes, is preferably between approximately 7.5 mm
and 8.5 mm in diameter so that the smoking system 21 provides a
smoker a familiar "mouth feel". In the preferred embodiment, the
cigarette 23 is approximately 62 mm in overall length, thereby
facilitating the use of conventional packaging machines in the
packaging of the cigarettes 23. The combined length of the
mouthpiece filter 94 and the free-flow filter 92 is preferably 30
mm. The tipping paper preferably extends approximately 6 mm over
the tobacco rod 60. The total length of the tobacco rod 60 is
preferably 32 mm. Other proportions, lengths and diameters may be
selected instead of those recited above for the preferred
embodiment.
The tobacco rod 60 of the cigarette 23 preferably includes a
tobacco web or mat 66 which has been folded into a tubular
(cylindrical) form.
An overwrap 71 intimately enwraps the tobacco web 66 and is held
together along a longitudinal seam as is common in construction of
more traditional cigarettes. The overwrap 71 retains the tobacco
web 66 in a wrapped condition about a free-flow filter 74 and a
tobacco plug 80.
Preferably, the cigarette overwrap paper 71 is wrapped intimately
about the tobacco web 66 so as to render external appearance and
feel of a more traditional cigarette. It has been found that a
better tasting smoke is achieved when the overwrap paper 71 is a
standard type of cigarette paper, preferably a flax paper of
approximately 20 to 50 CORESTA (defined as the amount of air,
measured in cubic centimeters, that passes through one square
centimeter of material, e.g., a paper sheet, in one minute at a
pressure drop of 1.0 kilopascal) and more preferably of about 30 to
45 CORESTA, a basis weight of approximately 23 to 35 grams per
meter squared (g/m.sup.2) and more preferably about 23 to 30
g/m.sup.2, and a filler loading (preferably calcium carbonate) of
approximately 23 to 35% by weight and more preferably 28 to 33% by
weight. The overwrap paper 71 preferably contains little or no
citrate or other burn modifiers, with preferred levels of citrate
ranging from 0 to approximately 2.6% by weight of the overwrap
paper 71 and more preferably less than 1%.
The tobacco web 66 itself preferably comprises a base web 68 and a
layer of tobacco material 70 located along the inside surface of
the base web 68. At the tipped end 72 of the tobacco rod 60, the
tobacco web 66 together with the overwrap 71 are wrapped about the
tubular free-flow filter plug 74. The free-flow filter 74 (also
known in the art as "whistle-through" plugs) provides structural
definition and support at the tipped end 72 of the tobacco rod 60
and permits aerosol to be withdrawn from the interior of the
tobacco rod 60 with a minimum pressure drop. The free-flow filter
74 also acts as a flow constriction at the tipped end 72 of the
tobacco rod 60, which is believed to help promote the formation of
aerosol during a draw on the cigarette 23. The free-flow filter is
preferably at least 7 millimeters long to facilitate machine
handling and is preferably annular, although other shapes and types
of low efficiency filters are suitable, including cylindrical
filter plugs.
At the free end 78 of the tobacco rod 60, the tobacco web 66
together with the overwrap 71 are wrapped about a cylindrical
tobacco plug 80. Preferably, the tobacco plug 80 is constructed
separately from the tobacco web 66 and comprises a relatively short
column of cut filler tobacco that has been wrapped within and
retained by a plug wrap 84.
Preferably the tobacco plug 80 is constructed on a conventional
cigarette rod making machine wherein cut filler (preferably
blended) is air formed into a continuous rod of tobacco on a
traveling belt and entrapped with a continuous ribbon of plug wrap
84 which is then glued along its longitudinal seam and heat sealed.
In accordance with the preferred embodiment of the present
invention, the plug wrap 84 is preferably constructed from a
cellulosic web of little or no filler, sizing or burn additives
(each at levels below 0.5% weight percent) and preferably little or
no sizing. Preferably, the tobacco plug wrap 84 has a low basis
weight of below 15 grams per meter squared and more preferably
about 13 grams per meter squared. The tobacco plug wrap 84
preferably has a high permeability in the range of about 20,000 to
35,000 CORESTA and more preferably in the range of about 25,000 to
35,000 CORESTA, and is constructed preferably from soft wood fiber
pulp, abaca-type cellulose or other long fibered pulp. Such papers
are available from Papierfabrik Schoeller and Hoescht GMBH,
Postfach 1155, D-76584, Gernsback, GERMANY; another paper suitable
for use as the plug wrap 84 is the paper TW 2000 from DeMauduit of
Euimperle FRANCE, with the addition of carboxy-methyl cellulose at
a 2.5 weight percent level.
The tobacco rod making machine is operated so as to provide a
tobacco rod density of approximately 0.17 to 0.30 grams per cubic
centimeter (g/cc), but more preferably in a range of at least 0.20
to 0.30 g/cc and most preferably between about 0.24 to 0.28 g/cc.
The elevated densities are preferred for the avoidance of loose
ends at the free end 78 of the tobacco rod 60. However, it is to be
understood that the lower rod densities will allow the tobacco
column 82 to contribute a greater proportion of aerosol and flavor
to the smoke. Accordingly, a balance must be struck between aerosol
delivery (which favors a low rod density in the tobacco column 82)
and the avoidance of loose-ends (which favors the elevated ranges
of rod densities).
The tobacco column 82 preferably comprises cut filler of a blend of
tobaccos typical of the industry, including blends comprising
bright, burley and oriental tobaccos together with, optionally,
reconstituted tobaccos and other blend components, including
traditional cigarette flavors. However, in the preferred
embodiment, the cut filler of the tobacco column 84 comprises a
blend of bright, burly and oriental tobaccos at the ratio of
approximately 45:30:25 for the U.S. market, without inclusion of
reconstituted tobaccos or any after cut flavorings. Optionally, an
expanded tobacco component might be included in the blend to adjust
rod density, and flavors may be added.
The continuous tobacco rod formed as described above is sliced in
accordance with a predetermined plug length for the tobacco plug
80. This length is preferably at least 7 mm in order to facilitate
machine handling. However, the length may vary from about 7 mm to
25 mm or more depending on preferences in cigarette design which
will become apparent in the description which follows, with
particular reference to FIG. 7.
As a general matter, the length of the tobacco plug 80 is
preferably set relative to the total length of the tobacco rod 60
such that a void 91 is defined along the tobacco rod 60 between the
free-flow filter 74 and the tobacco plug 80. The void 91
corresponds to an unfilled portion of the tobacco rod 60 and is in
immediate fluid communication with the tipping 62 through the free
flow filter 74 of the tobacco rod 60.
Referring particularly to FIG. 6, the length of the tobacco plug 80
and its relative position along the tobacco rod 60 is also selected
in relation to features of the heater elements 37. When a cigarette
is properly positioned against a stop 182 within the lighter 25, a
portion 93 of each heater element 37 will contact the tobacco rod
60 along a region of the tobacco rod 60. This region of contact is
referred to as a heater footprint 95. The heater footprint 95 (as
shown with a double arrow in FIG. 2) is not part of the cigarette
structure itself, but instead is a representation of that region of
the tobacco rod 60 where the heater element 37 would be expected to
reach operative heating temperatures during smoking of the
cigarette 23. Because the heating elements 37 are a fixed distance
96 from the stop 182 of the heater fixture, the heater foot print
95 consistently locates along the tobacco rod 60 at the same
predetermined distance 96 from the free end 78 of the tobacco rod
60 for every cigarette 23 that is fully inserted into the lighter
25.
Preferably, the length of the tobacco plug 80, the length of the
heater footprint 95 and the distance between the heater footprint
95 and the stop 182 are selected such that the heater footprint 95
extends beyond the tobacco plug 80 and superposes a portion of the
void 91 by a distance 98. The distance 98 by which the heater
footprint 95 superposes the void 91 (the unfilled portion of the
tobacco rod 60) is also referred to as the "heater-void overlap"
98. The distance by which the remainder of the heater footprint 95
superposes the tobacco plug 80 is referred to as the "heater-filler
overlap" 99.
The tipping 62 preferably comprises a free-flow filter 92 located
adjacent the tobacco rod 60 and a mouthpiece filter plug 94 at the
distal end of the tipping 62 from the tobacco rod 60. Preferably
the free-flow filter 92 is tubular and transmits air with very
little pressure drop. Other low efficiency filters of standard
configuration could be used instead, however. The inside diameter
for the free flow filter 92 is preferably at or between 2 to 6
millimeters and is preferably greater than that of the free flow
filter 74 of the tobacco rod 60.
The mouthpiece filter plug 94 closes off the free end of the
tipping 62 for purposes of appearance and, if desired, to effect
some filtration, although it is preferred that the mouthpiece
filter plug 94 comprise a low efficiency filter of preferably about
15 to 25 percent efficiency.
The free-flow filter 92 and the mouthpiece filter plug 94 are
preferably joined together as a combined plug with a plug wrap 101.
The plug wrap 101 is preferably a porous, low weight plug wrap as
is conventionally available to those in the art of cigarette
making. The combined plug is attached to the tobacco rod 60 by the
tipping paper 64 of specifications that are standard and
conventionally used throughout the cigarette industry. The tipping
paper 64 may be either cork, white or any other color as decorative
preferences might suggest.
Preferably, a cigarette 23 constructed in accordance with the
preferred embodiment has an overall length of approximately 62 mm,
of which 30 mm comprises the combined plug of the tipping 62.
Accordingly, the tobacco rod 60 is 32 mm long. Preferably, the
free-flow filter 74 of the tobacco rod 60 is at least 7 mm long and
the void 91 between the free-flow filter 74 and the tobacco plug 80
is preferably at least 7 mm long. In the preferred embodiment, the
heater foot print 95 is approximately 12 mm long and located such
that it provides a 3 mm heater-void overlap 98, leaving 9 mm of the
heater foot print 95 superposing the tobacco plug 80.
It is to be understood that the length of the void 91, the length
of the tobacco plug 80, and the distribution of the perforation
holes 263 may be adjusted to facilitate manufacturing and more
importantly, to adjust the smoking characteristics of the cigarette
23, including adjustments in its taste, draw and delivery. The
pattern of holes 263, the length of the void 91 and the amount of
heater-filler overlap (and heater-void overlap) may also be
manipulated to adjust the immediacy of response, to promote
consistency in delivery (on a puff-to-puff basis as well as between
cigarettes) and to control condensation of aerosol at or about the
heaters.
In the preferred embodiment, the void 91 (the filler-free portion
of the tobacco rod 60) extends approximately 7 mm to assure
adequate clearance between the heater foot print 95 and the
free-flow filter 74. In this way, margin is provided such that the
heater foot print 95 does not heat the free-flow filter 74 during
smoking. Other lengths are suitable, for instance, if manufacturing
tolerances permit, the void 91 might be configured as short as
approximately 4 mm or less, or in the other extreme, extended well
beyond 7 mm so as establish an elongate filler-free portion along
the tobacco rod 60. The preferred range of lengths for the
filler-free portion (the void 91) is from approximately 4 mm to 18
mm and more preferably 5 to 12 mm.
Referring to FIG. 7, a preferred method of manufacturing cigarettes
23 in accordance with a preferred embodiment of the present
invention may initiate with the production of a plug comprising a
multiple of tobacco plugs 80, preferably in a 2-up configuration
and enwrapped with the plug wrap 84.
It is to be understood that reference to a 2-up tobacco plug 80
refers to a plug construction such that if it were divided into two
pieces, would render two complete tobacco plugs 80 of the preferred
cigarette 23. Likewise, a 2-up tipping plug 62, if separated into 2
pieces, would provide a pair of tippings 62, each comprising
free-flow filter 92, a mouth piece filter 94 and a plug wrap 84 as
described in connection with the partially-filled cigarette 23 of
the preferred embodiment. As a further example, a 2-up tobacco rod
plug 60, if severed, would render two complete tobacco rods 60.
Referring back to FIG. 7, production of the 2-up tobacco rod plugs
60 initiates with the construction of 2-up tobacco plugs 80 and the
establishment of a supply of 12-up free-flow filter plugs 74.
Preferably the tobacco plug 80 is constructed on a conventional
cigarette rod making machine 122 (such as a Molins Mark 9 tobacco
rod maker) wherein cut filler (preferably blended) is air formed
into a continuous rod of tobacco on a traveling belt and enwrapped
with a continuous ribbon of plug wrap 84 which is then glued along
its longitudinal seam and heat sealed. The output of the tobacco
rod maker 122 is then cut at a cutter 124 and delivered by a
suitable arrangement 126 to a first hopper 128 of a combining
machine such as a Molins double-action plug-tube combiner. The
delivery arrangement 126 may include a HCF tray filler or some
other equally suitable arrangement to load the first hopper 128
with the 4-up tobacco plugs 80. Other suitable plug delivery
systems might be employed such as mass flow conveyors or pneumatic
tubes or the like.
Similarly, the 12-up free-flow filter plugs 74 are produced in
continuous fashion from a tubular filter rod maker 130, such as
with a maker as described in U.S. Pat. No. 3,637,447 to Berger et
al, particularly at column 4. The continuous rod of tubular filter
material from the rod maker 130 is cut at a cutter 132 into the
12-up free-flow filter plugs 74 and delivered to a second hopper
134 of the Molins double-action plug-tube combiner ("DATPC ") via a
suitable delivery arrangement 136 which preferably comprises a HCF
tray filler, although other delivery arrangements as previously
described might be used instead.
The 12-up free-flow filter plugs 74 from the second hopper 134 are
cut into six 2-up free-flow filter plugs 74 and the 4-up tobacco
plugs from the first hopper 128 are cut into two 2-up tobacco plugs
80. These 2-up tobacco plugs 80 and 2-up free-flow filter plugs 74
are then placed in alternating relation to one another upon a
conveyor 140 leading to a garniture belt 142. Such mechanical
action can be provided at the front end of a Molins DAPTC combiner.
The spacing between the 2-up tobacco plugs 80 and the 2-up
free-flow filter plugs 74 is set to equal the desired amount of
void 91 desired in the tobacco rod 60 of the cigarette 23 being
produced.
In most Molins DAPTC combiners, this spacing 91 between the 2-up
plugs on the conveyor 140 is set precisely with a collator/spacer
drum 139 located at or about the location where the compression
belt 141 and the garniture belt 142 receive the 2-up free-flow
filter plugs 74 and the 2-up tobacco plugs 80. Other suitable
arrangements for assuring proper placement of the 2-up plugs 74 and
the 2-up tobacco plugs 80 would be readily apparent to one of
ordinary skill in the art of combining plugs.
Just upstream of the garniture belt 142, a continuous ribbon of
tobacco web 66 is reeled from a bobbin 144 through a series of
slack and tension controlling rollers generally designated 146 and
past a glue applicator 148 prior to its arrival at the final roller
150, which then directs the ribbon of tobacco web 66 toward the
path of the garniture belt 142.
Likewise, a continuous ribbon of overwrap 71 is reeled from a
bobbin 152 through an arrangement for adjusting slack and/or
tension in the ribbon 71 generally designated 154, past a plurality
of glue applicators 156 and then about a final roller 158 which
directs the ribbon of overwrap 71 toward the path of the garniture
belt 142 and between the garniture belt 142 and the tobacco web
66.
During passage through the garniture 160, the continuous ribbon of
tobacco web 66 and the overwrap 71 are folded about the spaced
apart 2-up tobacco plugs 80 and the 2-up free-flow filter plugs 74
to produce a continuous rod 162 which is then cut at the cutter
head of the DAPTC machine to produce tobacco rod portions 164. The
cutter head 166 is arranged to cut every other 2-up tobacco plug 80
so as to produce 2-up tobacco rods 164 having a 1-up tobacco plug
80 at opposite ends thereof and a 2-up free-flow filter 74
separated from the tobacco plugs 80 by spaces 91. The 2-up tobacco
rods 164 are delivered from the output of the combining machine to
a drum link-up assembly 220 which cuts the 2-up tobacco rods in
half to form tobacco rods of unit length and delivers the cut
tobacco rods to an assembly drum of the tipping apparatus.
The apparatus according to the invention eliminates the need to
load cut tobacco rods into a hopper of a tipping machine and
thereby minimizes damage which could occur to the tobacco rods
during transport through such a hopper system. For instance,
commonly-owned U.S. Pat. No. 5,666,976 discloses an arrangement
wherein 4-up tobacco rods are delivered to a tray filler and then
to a hopper of a tipping machine wherein the 4-up tobacco rods are
transported through a series of drums which effect cutting of the
4-up tobacco rods into 2-up tobacco rods and then into 1-up tobacco
rods. Such an arrangement exposes the 4-up tobacco rods to
mechanical abrasion which can damage the tobacco rods. The
apparatus according to the invention obviates the need for a hopper
to receive the tobacco rods since the output of the combining
apparatus wherein the tobacco rods are manufactured is directly
linked to the tipping machine by the drum link-up assembly.
The DAPTC machine shown in FIG. 7, is hard-linked to the cigarette
tipping machine 200 (shown in FIG. 9) by the drum link-up assembly
220. The drum link-up assembly can be comprised of a plurality of
drums in any suitable arrangement. A preferred arrangement which
allows optional laser perforation of the tobacco rod is shown in
FIG. 9. It should be appreciated that this connection between the
DAPTC machine and the tipping machine 200, allows for a smooth
transition from the DAPTC to the tipping machine 200 in a quick and
efficient manner.
Referring back to the garniture 160 of FIG. 7 and in specific
reference to FIGS. 8A-8E, as the various components of the tobacco
rod 60 are pulled through the garniture 160, a progression of
folding steps wraps the continuous ribbon of tobacco mat 66 and the
continuous ribbon of overwrap 71 about the alternating succession
of 2-up plugs 80 and 74.
Referring now to FIG. 8A, upon their arrival at the garniture belt
142, the plugs 74 and 80, the tobacco web 66 and the overwrap 71
are urged against one another and the garniture belt 142 by the
compression belt 141. A continuous bead of adhesive 172 is located
at or about the center region of the continuous ribbon of tobacco
web 66 as applied by the glue applicator 148. This bead of adhesive
172 anchors the 2-up tobacco plugs 80 and 2-up free-flow filter
plugs 74 to the ribbon of tobacco web 66.
Likewise, a glue applicator can be used to lay down intermittent
beads of adhesive or plural glue applicators 156 can be used to lay
down continuous beads of adhesive 174, 176 and 178 on the side 180
of the continuous ribbon of overwrap 71 which is to come into
contact with the continuous ribbon of tobacco web 66 at the
garniture 160. It is preferred that these "laminating" beads of
adhesive 174, 176 and 178 are not allowed to set prior to entry
into the garniture 160 so the tobacco web 66 and the overwrap 71
may slip slightly relative to one another as they are folded about
the 2-up plugs 80 and 74 in the garniture 160. This provision for
at least some "give" avoids breaks and tears in the materials.
Referring now to FIGS. 8B and 5C, the garniture 160 progressively
folds the continuous ribbon of tobacco web 66, together with the
continuous ribbon of overwrap 71 about the 2-up plugs 74 and 80. It
is to be noted that the relative placements of the tobacco web 66
and the overwrap 71 are slightly offset from one another so that
along one side of the plugs 74 and 80 an edge portion 182 of the
overwrap 71 extends only slightly beyond the adjacent edge of the
tobacco mat 66, preferably at about 1 millimeter or so, whereas
along an opposite side of the plugs 74 and 80, an edge portion 384
of the overwrap 71 extends at least several millimeters beyond the
adjacent edge of the tobacco web 66. Such provision allows for the
application of a bead of adhesive along the edge portion 184 by a
glue applicator 186 as shown in FIG. 8D, prior to the edge portion
184 being folded completely down and over the plugs 74 and 80 as
shown in FIG. 8E to form a seam 189.
It is to be noted that the tobacco web 66 is folded such and its
width is selected such that it does not overlap upon itself at its
seam 188. Preferably, no adhesive is applied at or about the seam
188 of the tobacco web 66 so as to minimize the application of
adhesive to the structure of the tobacco rod structure 60.
It has also been found effective to locate the laminating adhesive
beads 174, 176 and 178 at 4 o'clock, 6 o'clock and 8 o'clock
positions relative to the cross-sectional form of the 2-up plugs 74
and 80 at the garniture 160.
The preferred adhesive for all adhesive beads 174, 176, 178, 172
and 190 is a liquid starch adhesive such as obtainable from
National Starch. The bead of adhesive 190 is sufficiently strong
enough to retain the tobacco web 66 in its completely folded
condition.
According to a preferred embodiment, the output of the combining
apparatus is a 2-up tobacco rod plug 164 which is directly linked
to a catch drum 222 of the drum link-up assembly 220 at the
entrance to a cigarette tipping machine 200 such as a Hauni Max
that has been modified to operate in the manner as described with
reference to FIGS. 10A and 10B. A preferred layout of the modified
Hauni Max is shown in FIG. 9. However, other tipping machines or
the like could be arranged to execute the steps of cigarette
manufacture that are described below.
Referring now to FIGS. 9 and 10A-10B, a hopper 192 of the tipping
machine 200 receives 4-up tipping plugs 62 which are the product of
a combining operation 194 (FIG. 10A), wherein 2-up free-flow filter
plugs 92 from a tubular filter rod maker 196 and 2-up mouthpiece
filter plugs 94 from another filter rod maker 198, such as a KDF-2,
are combined, together with plug wrap 84, to produce the
aforementioned 4-up tipping plugs 62 (a plug which when severed
into four pieces provides four tippings 62, each comprising a
free-flow filter 92, a mouthpiece filter 94 and plug wrap 84). The
4-up tipping plugs 62 are delivered to the hopper 192 of the
tipping machine 200 by suitable delivery arrangement.
The description of further steps in the preferred method of
producing the cigarettes 23 will now be described with reference to
the relative movement and position of the cigarette components as
shown in FIGS. 10A-10B, with cross-reference to respective drum
stations along the mechanical pathway of the machine 200 as shown
in FIG. 9. FIGS. 10A-10B include dashed lines that bear
designations which correlate to drums in the machine 200 of the
same designation.
The 2-up tobacco rod portions 164 are transferred directly from the
combining apparatus to the drum link-up assembly 220. In the
embodiment shown in FIG. 9, the 2-up tobacco rods are transferred
to a catch drum 222 of the drum link-up assembly. The drums of the
drum link-up assembly include flutes for receiving tobacco rods and
vacuum arrangements which apply vacuum to the flutes at rotational
positions of the drums where it is desired to hold the tobacco rods
via suction. The vacuum is terminated at rotational positions of
the drum where it is desired to release the tobacco rods for
transfer to an adjacent drum. To facilitate transfer of the tobacco
rods from one drum to another, the drums rotate in opposite
directions, i.e., a tobacco rod traveling in a clockwise direction
on one drum is picked up by an adjacent drum rotating in a
counterclockwise direction after which the tobacco rod is picked up
by a drum rotating in a clockwise direction and so on.
As shown in FIG. 9, the next member to receive the tobacco rods 60
from the catch drum 222 is a transfer drum 224 which transfers the
tobacco rods onto the next component. The main purpose of the
transfer drum 224 is to properly orient the tobacco rods 164 to be
transferred to the next component. Another purpose of the transfer
drum is to allow the tobacco rods to be properly passed so a
desired delivery of the tobacco rods may be achieved due to the
rotation of the various drums. For example, the drum 232 in FIG. 9
currently is rotating in a counterclockwise direction.
Next, the tobacco rods are transferred to a swash-plate drum 226.
The main purpose of the swash-plate drum 226 is to center the
tobacco rods, and to properly align the tobacco rods, before the
tobacco rods are transferred to the next component.
Subsequently, the tobacco rods are transferred to a laser drum 228
which can be used to form perforations on the tobacco rods. The
laser drum 228 may be set up as needed by the user to create
perforations either circumferentially or longitudinally, but in the
preferred method the perforations are positioned circumferentially.
Any type of laser system may be used that can accomplish the
objective of creating perforations. However, the perforations can
be omitted or formed by another suitable technique.
After passing around the laser drum 228, the tobacco rods are
transferred to a cutting drum 230, wherein the tobacco rods are cut
by a cutter (not shown). In the preferred apparatus, the tobacco
rods are cut by a cutter which is rotating in a direction opposite
to that of the cutting drum 230. Preferably, the cutter cuts the
tobacco rods in half from a 2-up 64 mm tobacco rod to two 32 mm
tobacco rods 60, 60'.
After the tobacco rods 60, 60' are cut, to a length desired by the
user, the tobacco rods 60, 60' are transferred to a separator drum
232. The primary purpose of the separator drum 232 is to separate
the two tobacco rods 60, 60' to create a space between the two
tobacco rods 60, 60' so that a 2-up tipping plug 62 may be placed
in between the two tobacco rods 60, 60'.
The tipping plugs are combined with the tobacco plugs as follows.
First, 4-up tipping plugs 62 from the hopper 192 are delivered onto
a third cutting drum 242 and cut into two, 2-up tipping plugs 240
and 240'. Each 2-up tipping plug 240 comprises a 1-up free-flow
filter 92 at one end, a centrally located 2-up mouthpiece filter 94
and another 1-up free-flow filter 92 at the other end of the 2-up
tipping plug 240.
The 2 two-up tipping plugs 240 and 240' are then graded at a
grading drum 244 and aligned on a alignment drum 246. The aligned
two-up tipping plugs 240 and 240' are then transferred through an
accelerator drum 248 onto a central portion of the assembly drum
238 so as to locate the 2-up tipping plugs 240 and 240' centrally
between the pairs of separated tobacco plugs 60, 60'. At the
conclusion of this operation, on each flute of the assembly drum
238, the free ends of the free-flow filters 92 of a 2-up tipping
plug face the free-flow filters 74 of a separated pair of tobacco
rods 60'.
Next, the aforementioned components placed at the assembly drum 238
are transferred to a swash-plate drum 250 whose outer rail pushes
the associated pairs of tobacco rods 60, 60' into abutting
relationship with the respective 2-up tipping plug 240 situated
therebetween. Meanwhile, a continuous ribbon of tipping paper is
drawn from a bobbin 254 and directed through a glue applicator 255
and severed into double-wide pieces 256 at a cutter 257. Once the
cigarette components are positioned by the swash plate, an
edge-portion of a double-wide piece of tipping paper 64 is attached
to the respective 2-up tipping plug 240 and abutting portions of
the pair of tobacco rods 60, 60' so as to initiate connection of
these components to form 2-up cigarette rods 252. The tipping
operation is then continued on a roll drum 260 which rolls the
double-wide pieces of tipping paper 256 about the 2-up cigarette
rods 252. The 2-up cigarette rods 252 are then transferred to drum
261, wherein a plurality of perforations are optionally created on
the 2-up cigarette rods 252. In the preferred embodiment, the
perforations 263 are created by a laser system. The perforations
263 are oriented circumferentially around the cigarette rods 252,
and are preferably located anywhere from 4 mm to 20 mm, e.g. 4 to
12 mm from the free end 15 of the cigarette such that the
perforations extend into the tobacco plugs 80. The rods 252 are
then cut in two at a final cut drum 262 to produce a pair of
cigarettes 23 and 23' from each of the rods 252. At a turning drum
264, one of the cigarettes 23 is turned and aligned with the other
cigarette 23'.
The continuous stream of cigarettes 23 produced from the tipping
machine 200 is then directed to packers 266 and cartoners 268 and
finally case packers 270 for shipment from the manufacturing
facilities.
It will be understood that any type of perforating system can be
used to perforate the tobacco rods prior to being attached to the
filter rods and/or after the tobacco rods are attached to the
filter rods. A preferred perforating system is a laser perforating
system, many forms of which are available commercially. FIG. 11
shows a perspective side view of portions of a Hauni 500 laser
perforating system which is commercially available from Hauni
Maschinenbau AG, located in Hamburg, Germany. According to the
invention, the laser system can be used to burn perforation holes
in tobacco rods at a location in the drum link-up assembly 220
located between a combining apparatus and a tipping apparatus. In
addition, another Hauni 500 laser system can be used to burn
perforation holes in a tobacco rod of a completed cigarette at a
location near the exit of the tipping apparatus.
As shown in FIG. 11, the laser perforating apparatus 298 includes
the laser perforating drum 228, flutes 302 for holding tobacco rods
(or completed cigarettes in the case where the laser perforating
apparatus is located in the tipping apparatus), rolling cams 304
which engage the rods/cigarettes located in the flutes 304 so as to
roll the rods/cigarettes from a first portion of the flute to a
second portion of the flute (see FIG. 13), and a laser beam
directing device 306 which splits a laser beam into two beams for
perforating two locations on the tobacco rods/cigarettes. The
preferred location for burning the perforating holes in the 2-up
tobacco rods passing through the drum link-up apparatus 220 (or in
the tobacco rods of the completed cigarettes) is with an area
located 4 to 20 mm from the end of the tobacco rod at which the
tobacco plug 80 is located. With reference to FIG. 6, the
perforating holes 263 thus formed will pass through the tobacco rod
outer overwrap 71, the tobacco mat 66, the overwrap 84 surrounding
the tobacco plug 80 and into the tobacco plug 80.
FIG. 12 is a perspective view of the apparatus shown in FIG. 11 but
from an opposite side thereof. As shown in FIG. 12, the laser beam
directing device 306 includes a focusing device 308 wherein a
plurality of beams are focused on an individual tobacco rod 164.
Further details of the focus device 308 can be seen in FIGS. 13 and
14. As shown in FIG. 13, the focusing device directs a focused
laser beam 310 onto the tobacco rod 164 as the tobacco rod is
rotated about its axis along the surface of the flute 302 by the
rolling cam 304. The laser (not shown) is actuated by a controller
(not shown) which is programmed to deliver a pulsed beam during
rotation of the tobacco rod in the flute after which the beam is
shut off until the next tobacco rod is in a location suitable for
perforation by the beam. FIG. 14 shows a beam 312 from the laser
(not shown), a first mirror 314 for deflecting a portion of the
beam 312 to a first lens 316, and a second mirror 318 for
deflecting a second portion of the beam 312 to a second lens 320.
As a result, the beam splitter arrangement shown in FIG. 14 directs
a pair of beams onto the 2-up tobacco rod 164 at locations near the
free ends thereof.
The laser system can be set up to provide any desired perforation
hole pattern in the tobacco rods. According to a preferred
embodiment, the laser is programmed to burn 12 to 24 holes having a
width of about 0.06 mm into the outer surface of each tobacco rod.
The holes can be provided in a single row or multiple rows
extending around the circumference of the tobacco rod and depending
on the length of the laser pulse width (the amount of time the
laser is in the "on" portion of a pulse cycle), the length of the
holes in the circumferential direction can vary accordingly.
Further, the row or rows can be provided at longitudinally spaced
apart locations along the tobacco rod. For example, a row of
perforations could be provided at a location about 4 mm from the
end of the tobacco rod and another row of perforations could be
provided at a location about 7 to 12 mm from the end. Moreover, by
focusing the beam such that the focal point is inside the tobacco
rod, a pair of adjacent holes can be burned into the tobacco rod
during each pulse of the laser, i.e., a single beam focused in this
way can provide a double row of perforations extending around the
tobacco rod.
In terms of operational parameters, the laser system should be
capable of penetrating the outer layers of the tobacco rod and
provide a desired pattern of holes while the tobacco rods travel
through the drum link-up assembly at speeds capable of producing
over 4000 rods/cigarettes per minute. As an example, a 300 watt
laser having a pulse duration of 1000 .mu.s can be operated with a
pulse width of 200 to 400 .mu.s (the amount of time the laser is
"on" during the pulse duration) to obtain a single or double row of
perforations in a 2-up tobacco rod traveling through the drum
link-up assembly at a speed sufficient to produce 5000 cigarettes
per minute. In such a system, a double row of 24 perforations with
12 perforations in each row can be obtained using a pulse width of
400 .mu.s. However, the actual power settings used will depend on
the particular laser system and the set-up associated
therewith.
FIG. 15 shows a schematic layout of a combining apparatus (DAPTC)
400, a link-up 402, a first laser perforating station 404, a
tipping apparatus (MAX S) 406, a second laser perforating station
408, and a conveying apparatus 410 for transporting, loading and
packaging the finished cigarettes. As shown, the DAPTC 400 conveys
tobacco rods in a direction perpendicular to the direction in which
the tobacco rods are attached to filter rods in the tipping
apparatus.
It is to be understood that the present invention may be embodied
in other specific forms and process the use without departing from
the spirit or essential characteristics of the present invention.
For example, the cutting and slitting operations may be
reconfigured to cut different multiples of plugs. Although the
disclosure specifies certain machines as being preferred, one of
ordinary skill in the art, once familiar with these teachings,
would be able to select other machines for executing the disclosed
process. Additionally, certain plug structures might be altered
such as replacing tubular plugs with those that may have a filled
central portion. Thus, while the invention has been illustrated and
described in accordance with various preferred embodiments, it is
recognized that variations and changes may be made therein without
departing from the invention as set forth in the claims.
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